New SVHC-free chip encapsulation adhesives

Easy and trustworthy access to SVHC-free adhesives made in the EU will become essential if, (or more likely when) industry regulations come into force banning the manufacture of such products.  Electronics engineers should note that DELO’s exclusive distributor in the UK & Ireland, Inseto can now supply its MONOPOX GE6585 and GE6525 materials, which are primarily used for Dam & Fill chip encapsulation. DELO DUALBOND GE7065 is also now available from Inseto, which is mainly used for Glob Top chip encapsulation. 

All three can be used for encapsulating not only semiconductor dies but also sensors too, a common practice in the automotive, aerospace and other harsh environments in industrial applications. Inseto Director Eamonn Redmond observes “Whilst not all chip encapsulation adhesives contain SVHCs, those that are needed to ensure high reliability do, and the European Chemical Association is constantly reviewing and working towards banning the use of SVHCs. Whilst it’s not certain when adhesives containing SVHCs will be banned they almost certainly will be. In addition, these new adhesives we now have offer significant processing and performance upgrades over their SVHC-containing counterparts.”

All three new adhesives have high shear strengths says Inseto, combined with low coefficients of thermal expansion (CTE), high glass transition temperatures (Tg), extended operating temperature ranges and an extremely high resistance to chemicals. GE6585 and GE6525 are one-part heat-cured black epoxies. Compared to their SHVC-containing counterparts, the CTE has been nearly halved. However, the new adhesives retain the extremely high Tg of the existing adhesives (>170oC), making them ideal for high reliability applications; ensuring minimal risk of board warpage during assembly.

GE7065 is also a one-part heat-cured black epoxy with a low CTE and high Tg. It also has the added advantage, says Inseto, of being light-fixable (optional) immediately after dispensing. In addition, the filler particle size is significantly reduced (to around 7μm), allowing the adhesive to flow more easily between very fine-pitch wire bonds. All three new adhesives boast significantly shorter curing times than their SVHC-containing counterparts – 30 minutes at 100 degrees Celsius for GE6585 and GE6525, and 60 minutes at 130 degrees Celsius for GE7065.